The architectural world was a cabinet of curiosities this week, starting with the opening of the long-awaited glass and ceramic-clad extension of the Holburne Museum in Bath. Designed by Eric Parry, this casket-like building is filled with the collection of art and curios gathered by Sir William Holburne (1793-1874), who saw action as an 11-year-old sailor on board HMS Orion at the battle of Trafalgar. (Collecting must have been a relief after that.) Working with exhibition designers Metaphor, Parry has conjured dramatic galleries, aptly reflecting the displays: a sequence of tiny rooms that surprise the visitor when they suddenly open up into double-height spaces. This is a trick Parry learned from Sir John Soane's Museum in Lincoln's Inn Fields, one of the most magical of all collector's treasure troves. On the top floor of the Holburne Peter Blake's temporary exhibition, A Museum for Myself, features General Tom Thumb's boots, Ian Dury's rhythm stick and the mannequin of Sonny Liston that appeared, centre stage, on Blake's cover for the Beatles' Sergeant Pepper's Lonely Hearts Club Band.

Honey's design for Duchamp on Regent Street. Photograph: RIBA

Over in central London, the shop windows of Regent Street have become a display of architectural curios until 29 May, as part of the RIBA Regent Street Windows Project. Ten architectural practices have dressed 10 windows for 10 shops: Aquascutum, Banana Republic, National Geographic, Duchamp, Ferrari, Gant, Hoss Intropia, Levi's, Ted Baker and Uniqlo. For Duchamp, Honey architects have designed a pattern of colourful geometric forms, a "breathing kaleidoscope" arranged so that "colours, shapes, objects, lights and the images of onlookers are revealed and obscured as it cycles from inhale to exhale". Best try seeing for yourself. Duggan Morris, meanwhile, have come up with a showcase of automotive components for the Ferrari shopfront that hints at shapes, forms and buildings found in city streets: fun, even if you come to Regent Street by bus or bike rather than a 200mph supercar.

The most curious new building to be unveiled this week is the Bella Sky Hotel in Copenhagen; the biggest hotel in Scandinavia, its twin 76.5m towers lean 15 degrees from the vertical (that's a lot more than the tower of Pisa). The hotel's architects, 3XN, also won the competition to design the nearly finished Museum of Liverpool, but fell from grace in 2007 when the project was taken over by the Manchester-based firm AEW after a dispute. According to the Architects' Journal, the musuem has issued legal proceedings against 3XN this week.

An artist's impression of 20 Fenchurch Street, aka the Walkie-Talkie

Back in London, Zaha Hadid told Building magazine she is ready to capture the city's skyline with her own brand of adventurous skyscrapers (she has yet to erect a tall building in London or indeed anywhere else in Britain). That skyline is certainly getting more clown-like by the day as Rafael Viñoly's curious 37-storey Walkie-Talkie office tower creeps towards completion. This week, the design was protected by the City of London Corporation from "rights of light", meaning the owners of seven buildings set to stand in its shadow will be unable to protest over their loss of daylight – the one thing that might have stopped the tower from wobbling up over them.

Let me know below what you've seen or heard about in the world of architecture and design this week – whether curious or beautiful, rational or bizarre. Please include links if possible and I'll round up the best next week.